# 17-身份运算符.py
'''
    is
    is not
    id() 获取变量的存储地址（唯一）
'''
a=10 
b=a
print(a,b)
print(a is b) 
print(id(a),id(b)) 
list = [1,2,3,4]
arr = list
arr[0]=666
print(arr,list) # 因为内存地址一样，导致都修改
arr=list[:] # arr 就会在内存中开辟新空间

